3 brilliant ways to breeze through the mid-afternoon slump and have more energy all day

You were having a productive morning at the office when suddenly, all you want to do is curl up under your desk and sleep.

The afternoon slump is perfectly natural - it's a sign your internal clock is working (yay!) and that your blood sugar levels are responding to the food you're eating.

No time for a nap? Here's how to trick your body into staying alert and breezing through the mid-afternoon crash.

1. Don't overdo it

While sugar-heavy or carb-heavy foods can leave you feeling shaky and tired in a few hours, high-fat foods can slow us down.

After we ingest too many empty carbs - foods high in sugar but low in protein - our blood-sugar levels spike; when they plummet a few hours later, we experience a "crash" in energy levels.

And unlike carbs, which make our blood-sugar levels erratic, fats digest very slowly. Eating too much of them in one sitting can make us feel tired because our bodies have to work harder to break them down.

Several recent studies also suggest the sugar and other carbs in food have a more direct impact on a specific group of brain cells called orexin neurons that help keep us awake. Large amounts of sugar in the blood may turn these cells off, making us sleepy.

So instead, eat a balanced lunch that has almost an equal amount of protein and carbs, like a turkey sandwich. The protein helps protect your blood sugar from sharp peaks and falls and keeps your energy levels steady. Then, have smaller, well-spaced meals throughout the day to keep blood-sugar levels stable.

2. Get some sun

Early exposure to bright light helps set our circadian rhythm for the day.

That's why taking in some natural rays right after we wake up can help us perform better later into the day, even in the middle of the afternoon, and help us sleep better at night.

Setting our circadian rhythms straight may also help steady our metabolisms. A recent study showed that people who basked in bright sunlight within two hours after waking tended to be thinner and better able to manage their weight, regardless of what they ate throughout the day.

3. Take a break

Moving around can help boost circulation and stimulate the mind.

A pair of Stanford scientists recently had two groups of volunteers take creativity quizzes in which they tried coming up with alternative uses for common objects, like a coffee cup or a pen. The first group sat at desks in a blank room; the other walked on a treadmill in that room. The students who walked came up with about 60% more uses for each object, and their ideas were not only creative but useful, the researchers wrote in their study.